Bike Maintenance

Bike Headset Repair

How to snug up a wobbly headset in less than 10 minutes

john olsen

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If your threadless bike headset has more chatter than a Sunday afternoon church social, it's probably loose. A rattling headset will make your steering sloppy—and if you don't fix the problem, the constant knocking will ovalize your head tube and ruin your frame. Prevent this by checking your bike's headset every other week with this quick test: Lock the front brake with your left hand and rock the bike forward and back while resting your right hand over the joint between the upper and lower parts of each headset bearing. If you feel front and back movement (or get your hand pinched by the shifting headset parts), you have a loose headset.

5 easy steps to end wobbles

1. Loosen the stem pinch bolts so that the stem moves freely on the fork's steerer. The bolts' size varies from 4mm to 6mm, depending on the type of stem.

2. Tighten the top cap bolt about one-quarter turn.

3. Tighten the stem pinch bolts and re-test for looseness. If there's still movement, loosen the pinch bolts and tighten the top cap bolt another quarter turn.

4. Once there's no play, check that the bike headset isn't too tight: Lift the bike off the ground and tilt it forward. Push the handlebar to one side and let it swing to a stop. If the wheel stops at an angle instead of pointing to the ground, the headset is too tight. Loosen the pinch bolts and back off the top cap bolt one-eighth turn. Tighten pinch bolts and re-test.

5. Bounce the front wheel to be sure the headset parts are seated. Test for looseness and tightness one more time.